Depth of tumor invasion independently predicts lymph node metastasis in T2 rectal cancer. - Ding, Pei-Rong; An, Xin; Cao, Yun; Wu, Xiao-Jun; Li, Li-Ren; Chen, Gong; Lu, Zhen-Hai; Fang, Yu-Jing; Wan, De-Sen; Pan, Zhi-Zhong (Journal of Gastrointestinal Surgery, 2011)